There's no audio in the video tutorial

If the course you purchased doesn't have audio, there are a few possible issues:

• Make sure your speakers are working. Play a video from YouTube, or a local song to test it. 
• There's a known issue with QuickTime and certain codecs causing audio issues. Try VLC instead. 
• The product wasn't intended to have audio. Certain products are simply timelapses without narration. Double check the product description for the product you bought and see if it mentions audio.
• Once you've checked all of the above, there's probably an issue with the actual videos. Make sure you contact the Creator before writing support. The Creator will have more information about their product and will be able to help you out faster :)